## A precise determination of top quark electro-weak couplings at the ILC operating at $\roots=500\,\GeV$    [PDF]

M. S. Amjad, M. Boronat, T. Frisson, I. Garcìa Garcìa, R. Pöschl, E. Ros, F. Richard, J. Rouëné, P. Ruiz Femenia, M. Vos
Top quark production in the process $e^+e^- \rightarrow t\bar{t}$ at a future linear electron positron collider with polarised beams is a powerful tool to determine indirectly the scale of new physics. The presented study, based on a detailed simulation of the ILD detector concept, assumes a centre-of-mass energy of $\roots=500$\,GeV and a luminosity of $\mathcal{L}=500\,\invfb$ equality shared between the incoming beam polarisations of $P_{e^{-,+}} =\pm0.8,\mp0.3$. Events are selected in which the top pair decays semi-leptonically. The study comprises the cross sections, the forward-backward asymmetry and the slope of the helicity angle asymmetry. The vector, axial vector and tensorial CP conserving couplings are separately determined for the photon and the $Z^0$ component. The sensitivity to new physics would be dramatically improved with respect to what is expected from LHC for electroweak couplings.
View original: http://arxiv.org/abs/1307.8102